This invention relates to safety guard assemblies for skylights. More particularly, the invention relates to safety guard assemblies for corrugated fiberglass reinforced plastic panels used to admit daylight through corrugated metal roofs.
For over thirty-five (35) years, translucent corrugated fiberglass reinforced plastic panels have been used to replace corrugated metal roof panels as a means for admitting daylight into the interior of buildings. Typically, only certain individual corrugated metal panels are replaced so that a sequence of alternating metal and plastic panels is created. In this manner, each plastic panel is encompassed and supported by adjacent metal panels. In addition, locating the plastic panels or skylights evenly over the roof provides an even illumination throughout the building. Since corrugated metal panels are made of a thin, light gauge sheet metal, the thickness of the corrugated plastic panels must also be of a light gauge in order to work in conjunction with the corrugated metal panels. A light gauge plastic panel is also necessary to allow enough passage of light to be effective as a skylight.
Corrugated plastic panels are usually reinforced with a fiberglass mat for additional strength. Since corrugated plastic panels must be made of a light gauge to begin with, the plastic resin used in these corrugated plastic panels is typically not light stable and can become brittle and suffer discoloration after a few years of ultraviolet exposure. After the plastic panel becomes brittle, the only significant material left to provide strength is the layer of fiberglass mat. However, the layer of fiberglass mat alone will not support the weight of a person.
For all of the reasons set out above, a person stepping onto a roof containing one or more corrugated plastic panels may be in real danger. Although a prudent person would be able to avoid intentionally stepping on such panels that he was aware of, there are a number of reasons for which a person might accidentally step on a weakened or embrittled plastic panel. For example, the plastic panels are at the same level as the rest of the roof and are not readily identifiable by looking at the roof, especially if the corrugated plastic panel has been painted to match the corrugated metal panel. Corrugated plastic panels are sometimes painted over when they become ineffective as a skylight due to the discoloration of the plastic panel. Moreover, if there is a thin layer of ice, snow, leaves or other debris on the roof a person can easily step or slide onto a corrugated plastic panel. If the panel is not strenthened or otherwise secured, there is a real hazard that a person may fall through.
The National Institute for Occupational Safety and Health (NIOSH) reports, in NIOSH Publication No. 90-100, that during the period 1980-85, 28 deaths resulted from falls through skylights and 39 deaths resulted from falls through roofs or roof openings. This danger is corroborated by the reports of the Occupational Safety and Health Agency (OSHA) which records the incidence of industrial and work related injuries. Report No. 91-660 describes an accident which occured in Grand Island, Nebr. to a painting contractor. The report states that the "[e]mployee was walking along a roof when he stepped into a roof skylight. He fell through the fiberglass skylight, 22 feet to the lower level, and was killed in the fall." A second report sets out a similar accident involving an employee of a refractory manufacturer. This report states that "[w]hile he was walking around a roof, victim stepped on a fiberglass covered skylight opening. He fell 25 feet to the floor below and was fatally injured."
Another OSHA report, ID 0352410, describes another incident as follows:
Several employees were reskinning a metal roof . . . located 20 feet above a concrete floor. The roof contained 8 uncovered fiberglass skylights, 11 feet by 3 feet. Employee #1, the foremen, had warned the other employees to be careful around the skylights. The job was 50% complete. It was a Friday, and the employees had started to clean up. Employee #1 dumped the water cooler and started to walk across the roof. He stepped onto a skylight and fell through it to the concrete floor. He died of massive head injuries. The skylights were not covered or otherwise guarded, and were painted the same color as the roof. PA1 Skylight screens shall be of such construction and mounting that they are capable of withstanding a load of at least 200 pounds applied perpendicularly at any one area on the screen. They shall also be of such construction and mounting that under ordinary loads or impacts, they will not deflect downward sufficiently to break the glass below them. The construction shall be of grillwork with openings not more than 4 inches long or of slatwork with openings not more than 2 inches wide with length unrestricted.
As a result of these and many other accidents involving skylights, OSHA has recognized the dangers posed by skylights and has promulgated requirements for a standard skylight screen in 29 C.F.R. 1910.23(e)(8) as follows:
The number of deaths and the resulting OSHA regulation illustrate that there exists a definite need for a cost effective means of guarding against falls through corrugated fiberglass skylights. The present invention is a skylight guard assembly that will prevent such tragic accidents from occurring.